GEHIR is an interdisciplinary research initiative at Masaryk University, Brno, which applies innovative methods used in the study of the dynamics of complex systems (mathematical and computational modelling, network science) to the historiography of ancient Graeco-Roman religions. Through focused case studies this initiative envisions an enrichment of the research into several religious domains of the ancient Mediterranean - Cults of Isis, Early Christianities, Hellenistic Judaism and Mithraism as well as a possibility for an exploration of the formalized modelling approaches in historiography and study of religions in general.

About the Project

A Generative Historiography of the Ancient Mediterranean: Modelling and Simulating the Diffusion of Religious Ideas and Forms of Behaviour

The project systematically applies selected methods of formalized modelling and computational simulations to the study of the diffusion dynamics of specific religious ideas and forms of behavior. As such, the project strives to integrate a specific methodological framework into the academic study of religion. On the one hand, this framework may open up new avenues in the systematic study of specific instances of historical change, on the other, it may contribute to the study of more general questions related to the factors which influence the dynamics of cultural systems.

This project is centred around case studies which focus on selected religious traditions of the ancient Mediterranean (Isiac cults, Mithraism, Hellenistic Judaism and early Christianities), which can be, despite their historical specificity, viewed through the same theoretical-methodological optics, i.e. through the processes of (1) the dissemination of religious ideas and forms of behaviour at the population level, (2) taking place over long periods of time, (3) being studied on the basis of fragmentary sources, (4) being viewed from the theoretical concept of the diffusion of innovations, (5) and being subjected to the influence of specific environmental, social and cognitive factors. These case studies were selected on the basis of their similarity as well as their complementary specificities. In this sense, the project aims at the foundation of a “methodological laboratory” whose probes might facilitate the work of other researchers, as it combines historiography with methods of formalized modelling.

Within the study of historical processes formalized modelling is conceptualised as an innovative third way through which the limitations of the traditional inductive analysis of historical sources and deductive application of social-scientific and cognitive theories to social and historical phenomena can be overcome. Computational modelling can be viewed as a form of theoretical experimentation that allows the process of explaining religion to exceed the limits, given by the fragmentary nature of historical sources and by the impossibility of exposing socio-cultural and historical complexity to the traditional laboratory reduction.

Cooperations

Social Media

Case Studies

ISIS-CULTS

DIRECTIONS FOR THE GODS: KEY FACTORS INFLUENCING THE EARLY SPREAD OF THE ISIAC CULTS

Early in the Ptolemaic era, the cult of Isis and Sarapis spread successfully to the ports in the ancient Mediterranean. However, the reasons standing behind this process are only partially understood. The main hypotheses in the academic discussion see the key factor influencing the spread of the Isiac cults as either the maritime trade network or Ptolemaic political propaganda. Both of these claims can find some support in the historical evidence. Ptolemaic Egypt was one of the main exporters of grain, Isis was a patron goddess of sailors and many cities in the ancient Mediterranean had close diplomatic relations with the Ptolemies. We are constructing a model in order to clarify which of these factors could be advantageous for specific locations in the question of the spread of the cult of Isis and Sarapis. Based on environmental and political datasets this model determines the theoretical political and trade atractiveness of these specific places for potential Egyptian visitors who could bring the cult practice or artifacts with them. The results of this model can be subsequently compared with the distribution of the archaeological evidence connected with the Isiac cults.

MARLUK

JEWISH AND NON-JEWISH NETWORKS IN THE SPREAD OF EARLY CHRISTIANITY: A CASE OF THE MARCIONATE AND LUKAN CHRISTIANITY

The influence of Jewish heritage on the spread of early Christianity represents a traditional research issue in the history of Christianity. However, research projects up to now have been mainly aimed at detailed analyses of fragmentary written sources and/or general reconstructions of historical process based on deductive methods. Modeling approaches based on network theory and/or discrete diffusion models can provide a more suitable way how to bridge the gap between the fragmentary historical evidence and the complexity of investigated processes.
The project is focused on the Marcionate and Lukan Christianities as a strictly coded test case dated back to the first half of the 2nd century. Despite weak historical evidence, it is obvious that these two trends, which are assumed to be contemporaneous (Pervo 2006; Tyson 2006), maintained different attitudes to the Jewish heritage and so they probably utilized different (i.e. Jewish and non-Jewish) networks. While the first trend, represented by Marcion and his canon (BeDuhn 2013), rejected the Jewish heritage, the latter one, represented by Luke and his writings, still maintained the Jewish background of Christianity.
Nuances of Judaizing and de-Judaizing tendencies are intentionally reduced to the Jewish and non-Jewish singular characteristics. It presupposes two crucial types of spreading dynamics which either used the Jewish networks or ignored them. This issue is now mathematically analyzed within the centralized and decentralized networks which might plausibly represent an ambivalent role of the Jerusalem centrality during the first two centuries of the spread of Christianity.

CHRISTROME

Christianization of the Roman Empire: Diffusion on a Settlement Network

At the beginning of the fourth century, Christians already constituted a substantial proportion of population of the Roman Empire, especially in eastern provinces, but also in Italy, north Africa or Spain. With its origins in 1st century Palestine, Christianity reached some locations earlier than others and blossomed in some places better than others. Using network analysis and computational models of the diffusion of innovations, our research project aims to evaluate several factors which could be responsible for the observed temporal and spatial distributions.
We hypothesize that the scarcely evidenced temporal and spatial distribution of Christianity over the Roman Empire can be re-grown in an artificial simulation environment as a diffusion of innovation model on a Roman travelling network of roads and maritime routes, which connects respective settlement sites to one another. We consider only (1) the travel expenses, (2) population sizes and economic importance of reachable destinations and (3) exponential grow of Christian number, while all the other environmental variables can be ignored for the sake of the analysis.
In the Graeco-Roman context, an adherence to a religious cult was typically expressed by one’s inclusion in a certain social unit (extended family, association etc.), rather than by personal decision and commitment to a set of beliefs. Therefore, Christianisation, too, can be approached on the level of practices of social groups instead than on the level of decisions of individuals. In that respect, by Christianisation we mean a twofold process: 1) by horizontal Christianisation we refer to a process concerning how worldviews and ritual innovations spread from one group to another; 2) by vertical Christianisation we refer to a process, not a moment, of continuous implementation of these innovations into the social practice of certain social group. At the current state of research, we are focusing more attention on the horizontal aspect.

MITHORIG

THE ORIGINS OF THE ROMAN CULT OF MITHRAS

The origins of the Roman cult of Mithras remain an unsolved puzzle. Since the Cumontian scenario (Cumont 1913), which holds that the Mithraic cult spread from ancient Persia to the Roman Empire, was abandoned due to increasing criticism, various alternative hypotheses have been presented. Some of these still assume that the formation of the cult took place in Asia Minor (e.g. Will 1978, Turcan 1993, Gordon 1978, Beck 1998). Others can be seen as a more radical departure from the Cumontian view and offer candidate regions more distant from ancient Persia, e.g. Bosporan Kingdom (Beskow 1978), Balkan Peninsula (Wikander 1951) or Rome/Ostia (Clauss 2000). However, the oldest archaeological evidence for the cultʼs existence does not unequivocally support any of these hypotheses; consequently, we cannot easily decide which of these scenarios of the origins of the Mithraic cult should be accepted as historically more likely. We argue that the analysis of the diffusion of Mithraic communities over the Mithraic network might possibly shed some light on the formation process of the Roman cult of Mithras and lead to the identification of a geographic region from where the cult probably began to spread, given its late distribution across the Roman Empire. The results of such an analysis may help scholars to evaluate competing scenarios of the Mithraic origins and to partially overcome the problem of the lack of relevant evidence. We assume that a quantitative network analysis of the spatial and temporal distribution of the archaeological and epigraphical evidence related to the Roman cult of Mithras may shed light on the process of the formation of the Roman cult of Mithras. This may lead to an identification of a geographic region from where the cult most likely started to spread. Results of such an analysis can help historians to better evaluate competing scenarios of Mithraic origins and partly “bridge“ lacunae caused by the lack of relevant evidence.

People

Aleš Chalupa

History of religions (Graeco-Roman religions, especially the Roman cult of Mithras, Graeco-Roman magic and divination), cognitive science of religion, cognitive historiography and new theoretical approaches to the study of (ancient) history, including mathematical and computational modelling as well as network analysis.

GEHIR Research Focus:

Aleš is working on the MITHORIG project (acronym for MIThraic ORIGins) focusing on the Roman cult of Mithras generally and more specifically on the vexed problem of its origins and initial propagation.

Dalibor Papoušek

History of religions (early Christianity, Second Temple Judaism), comparative study of religions, spatiality in ancient religions, archaeology and network analysis.

GEHIR Research Focus:

Dalibor is working on the MARLUK project (acronym for MARcionate and LUKan Christianity) which reconsiders the influence of the Jewish heritage in the spread of early Christianity throughout the Mediterranean. He hopes to use mathematical and computational network modeling to find a way to bridge the total lack of archaeological evidence in the formative period of Christianity.

Vojtěch is interested in the potential of quantitative methods to study the Christianization of the Roman Empire; he specifically focuses on the role of ritual innovations in that process. In his PhD. dissertation project, he aims to test particular hypotheses from cognitive theories of ritual while using the data concerning early Christian meal practices. In order to achieve this, he aims to use a set of agent-based models, which could be validated against the historical material. Apart the GEHIR project, he is also a member of the project REECR: Ritual and Emergence of Early Christian Religion: A Socio-Cognitive Analysis under the University of Helsinki.

Tomáš Glomb

History of religions (Hellenistic religions, especially the Isiac and royal cults under the early Ptolemies and the cult of Asclepius), cognitive archaeology, cognitive historiography, historical databases.

GEHIR Research Focus:

Tomáš is working on the ISIS-CULTS project focusing on uncovering the key factors standing behind the successful spread of the Isiac cults from Ptolemaic Egypt to the rest of the ancient Mediterranean.

Tomáš Hampejs

Cognitive science of religion, cultural transmission, ecological approaches to social cognition, generative social science, method and theory in the study of religions.

GEHIR Research Focus:

Tomáš is fascinated by epistemological aspects of different scientific imaginations and their methodological consequences. He tries to facilitate communication between team members and their disciplinary backgrounds. His ambition is to achieve an integrative meta-theoretical perspective towards individual research problems through iterative reflection of thinking shifts between different conceptual levels and scales.

Zdeněk Pospíšil

Differential and difference equations, time scales, mathematical modelling of real phenomena (ecology, evolution, epidemiology), philosophy and history of mathematics, probability and general questions of scientific reasoning.

GEHIR Research Focus:

Zdeněk is captivated by early Christianity - the absence of hard data is an opportunity for a deductive approach (i.e. a mathematical approach) to the problem. He hopes that his experience studying epidemiology, ecology and biological evolution can bring insight into cultural transmission, the competition of ideas, and non-designed phenomena in history.

As the one of cartographers in the GEHIR project, Adam is responsible for spatial data collection, map visualizations or geographic analyses. One of his motivations in the historiographical research is the possibility to work both with spatial and temporal aspect of information.

Zdeněk is focused on historical data spatial analysis and spatiotemporal cartographic visualization. His main research interest is cartographic representation of (un)certainty aspects of generated models.

Eva is interested in exploring the idea of using networks to better understand history and the processes of information spreading. She is currently investigating how the transport networks of the Ancient Mediterranean can provide insight into the diffusion of religious beliefs.

Jan focuses on computational models of dynamic processes in the Ancient Mediterranean. Specifically, he focuses on modeling the transport networks of the time and how they might address the sparse historical evidence related to the spread of religious beliefs and innovations.

David is an external advisor in the GEHIR project. He is currently working on the preparation of a related project that intends to use geographic information systems and social network analyses to facilitate research in medieval inquisitional records.